RADIOACTIVE 137CS CONTAMINATION OF THE MOSS-LICHEN COVER IN CONDITIONS OF FRESH PINE FORESTS

• Published in: Scientific Bulletin of UNFU
• Main Authors: Melnyk, V. V., Kurbet, T. V.
• Format: Article in Journal/Newspaper
• Language: Ukrainian
• Published: Ukrainian National Forestry University 2018
• Subjects: specific activity; transition factor; 137Cs; green (btyidea) mosses; epigeneous lichens; питома активність; коефіцієнт переходу; 137Сs; зелені (брієві) мохи; епігейні лишайники; Cladonia rangiferina
• Online Access: https://nv.nltu.edu.ua/index.php/journal/article/view/1550; https://doi.org/10.15421/40280318

Moss-lichen cover is an important component of forest biogeocoenoses, especially in coniferous forests. It serves as a peculiar depot on the way of migration, redistribution and accumulation of 137Cs in forest soils and other components of forest ecosystems. To study the modern radioactive contamination by the representatives of the moss-lichen cover, sample plots were laid in the Narodytsky SFH in the conditions of fresh pine forests where sampling was carried out of four types of epigeneous lichens, two species of green (btyidea) mosses and corresponding samples of soil. Before measuring 137Cs specific activity, all samples were dried to air-dry state and homogenized. The density of radioactive contamination of the soil within the sample plots varied in wide ranges from 315to 708kBq/m2. Correspondingly, certain fluctuations of the specific activity values for each species of moss and lichens were noted. For example, on the sample plots for Dicranum polysetum Sw. the average content of 137Cs was 11538±1022Bq/kg; for Pleurozium schreberi– 9312±679Bq/kg. The concentration of 137Cs in lichens varied in a wide range– from 3975to 9182Bq/kg. It was found that the specific activity of 137Cs for the Cladonia mitis is 1.5times less than for the Cladonia uncialis and Cladonia gracilis, and 1.1times less than for the Cladonia rangiferina. The Cladonia rangiferina accumulates 137Cs 1.4times less, compared to the Cladonia uncialis and Cladonia gracilis. The content of 137Cs in the phytomass of the Cladonia gracilis and Cladonia uncialis is almost the same. The amount of accumulation coefficient of 137Cs in lichens ranged from 3.2to 6.5, and in green mosses– from 3.8to 7.7. For the investigated species, we have also calculated the transition factor in the system of "soil-ground phytomass". The epigeneous lichens can be placed in the following order: Cladonia uncialis>Cladonia gracilis>Cladonia rangiferina>Cladonia mitis by the accumulation intensity of 137Cs. In the case of green mosses, for the Dicranum polysetum ...